PREVALENCE OF RESISTANCE TO 1ST LINE ANTI TUBERCULOSIS DRUGS AT RAHIM YAR KHAN

Abstract

Background: Tuberculosis is an important infectious health issue and its control strongly rely upon effective treatment. The drug
resistance and its pattern are important determinant of the treatment regimen, its duration and outcome. Objective: To determine
the frequency and pattern of drug resistance among 1st line anti tuberculosis treatment. Methodology: It was a cross sectional
study carried on 100 cases of smear positive TB. This study was conducted from 1st January 2010 to 30 June 2011. Detailed
demographic data and history of ATT was taken and their sputa were sent for drug susceptibility testing on LJ media. The cases
with drug resistance and no previous history of ATT were labeled as primary while those with previous history of ATT were
labeled as secondary resistant cases. The data was entered and analyzed by using SPSS version 15. Results: Out of 100 patients
enrolled, drug susceptibility report was available for 87 isolates as sputum failed to grow any organism in 13 patients. Out of these
87 cases, 48 (55.17%) were males and 39 (44.83%) females with age range of 9-91 years. Seventeen out of 87 patients (19.5%)
had previous history of ATT. Out of 87 isolate, 62 (71.26%) were sensitive to all 1st line drugs (R, H, E, Z, S) while 25 (28.74%)
were resistant to one or more drugs. Primary resistance was seen in 17 (24%) out of 70 cases in contrast to secondary in 8 (47%)
out 17. The difference between primary and secondary resistance among various drugs was statistically significant for isoniazid
(p value 0.003) and pyrazinamide (p value 0.036) while the difference to streptomycin, ethambutol and rifampicin was
insignificant with p values of 0.20, 0.35 and 0.09 respectively. There was no case of primary MDR-TB and 5.9% of secondary
MDR-TB. None of the sociodemographic parameter was significantly associated with drug resistance. Conclusion: Resistance
to 1st line anti-tuberculosis drugs at Rahim Yar Khan is still common. There are good number of patients in which this resistance
pattern compromise the currently recommended regimens. However, larger surveillance studies are needed to strengthen this
evidence.